Placer machine



March 30, 1937. .1. POORE 2,075,357

PLACER MACHINE Filed Feb. 17, 1934 I5 Sheets-Sheet 1 Ja/rw Poo/PE March 30, 1937. J. F. POORE 5,

PLACER MACHINE Filed Feb. 17, 1954 3 Sheets-Sheet 2 II I March 30, 1937. P g 2,075,357

I PLACER MACHINE Filed Feb. 17, 1954 5 Sheets-Sheet 3 Ker I Q :1 l vu on on Patented Mar. 30, 1937 UNITED STATES PAT-E NT ot-rice;

2 Claims.

This invention relates to a-placer machine or gold saver of the type adapted'to recover values from sand or crushed rock. The principal object of the invention is to .provide a simple, compact,

efficient, portable machine which will grade or .classify the incoming feed to the proper mesh, and which will efiiciently recover the values from the retained classification.

Another object of the invention is to provide an air draft which will assist gravity in separating the heavy particles or values from the sand.

Other objects are; to provide a machine'which can be operated, if. necessary, without water but in whichwater may be economic-ally used if available; to provide means for supplying the air and water pressure; to providea machine which will berreadily adjustable to suit various conditions and various sands; and which may be readily .cleaned to recover the retained values.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efiiciency. These will become more apparent from the following description.

In the following detailed description of the invention reference is had to the accompanying drawings which form a part hereof. Like numerals refer to like parts in all views of the drawings and throughout the description.

In the drawings:

Fig. 1 is a side elevation of the improved machine.

Fig. 2 is a detail view of the upper screenstructure thereof, taken on the line 2-2, Fig. 6.

Fig. 3 is an end elevation of the machine looking toward the discharge extremity.

Fig. 4 is a detail vertical longitudinal section through the upper extremity of the sluice tube.

Fig. 5 is a detail view, partly in section, ofthe sluice tube. v

Fig. 6 is a vertical section through the machine taken on the line 6-4;, Fig. 1.

Fig; 7 is a vertical section through the sluice tube taken on the line 1'|,-Fig. 3.

Fig. "8 is a'plan view of the machine with the screens partly broken away.

Fig. 9 is a detail view illustrating the type of conveyor chain employed in the machine.

Fig. 10 is an enlarged detail section through one of the sluice tube riflies.

The entire structure is supported on a suitable frame l0, provided with supporting legs upon which it may be set in any desired position. 55 Across the upper portion of the frame l0, two

screen shafts ll extend. Rocking levers l2 ride :upon the shafts .H adjacent each extremity of each. At the upper extremities of the .rocking levers I2, an upper screen frame 13 is carried,

and at the lower extremity thereof .is .a lower 5 iscreenframe M. It can be readily seen :that this arrangement causes :the screentframes l3 and 14 to move-in opposite directions if a movement is applied to either.

screen frame I1, is rigidly secured to and below the screen 13 upon suitable rigid hangers l8. Still another intermediate screen frame, which will be herein designated as the second screen frame I9, is similarlysecured to the screen frame s 14 upon suitable rigid hangers 20. It can be readily seen that this causes the upper screen frame and the third screen frame to move in unison ."in a. common direction, and the second screen frame and the lower screen frame to simi- 25 larly move in a common opposite direction.

The screen frames carry suitable wire cloth screens 2.l which successively decrease in mesh from the top to the bottom screen frame. All of the :frames are inclined toward the discharge 3-30 extremity of the machine and receive the sand to :be treated from a feed hopper 22 positioned over their upper extremities.

An endless conveyor chain or belt 23 ispositioned'immediately below the screens and extends .35 between suitable pulleys o-r sprockets/upon a drive shaft .24 and an idler shaft 25. The tension in the conveyor "23 can" be adjusted by means 'of a screw jack' 26 which moves the idler shaft "25. The drive shaft 24 may be rotated from any desired power source belted thereto on a drive pulley 21. It is important that the conveyor be of a substantially air tight construction so that the air blast will not blow the values through it. As illustrated, the conveyor, is 'formedby'securing a continuous series of overlapping slats 51 to the links of a pair of parallel conveyor chains. It could, however, be formed from a wide continuous band of belt material if desired.

A blower 28 is positioned in the frame II], the exhaust of which, is conducted through a conduit 29 upwardly along one side of the machine. It is thence conducted over the top of the upper screen 13 through a distributing hood 30 so as to blow downwardly through the entire series of screens. A distributing baffle 3| is positioned in the hood so as to distribute the pressure evenly over the screen surface. The blower is driven by means of a blower belt 32 from a relatively large pulley 33 on the drive shaft 24. The air is prevented from escaping through the sides I0 by means of suitable side plates 34 which are removably secured to the frame In in any desired manner such as by means of turn buttons 35.

In use, the sand or crushed rock is fed into the hopper 22 and feeds downwardly along the incline of the screens under the reciprocatory action of the eccentric IS. The coarser rock falls from the lower extremity of the upper screen, and the increasingly finer rock falls from the succeeding lower screens, allowing the very fine to fall to the conveyor 23. The action of gravity in carrying the heavier particles through the screens is assisted by the blast of air blowing downwardly from the hood l3 through the screens. Any adhering values in the sand will be blown free by this air and carried downwardly to the conveyor.

From the conveyor, the fine particles carrying the values flow into a receiving chute 36 and from thence into a sluice tube 31. The sluice tube 31 is hinged at 38 on the extremities of a bifurcated yoke 39 which in turn is mounted on a vertical hinge 40. This provides a universal joint for the sluice tube so that its free extremity may be turned in any desired vertical or horizontal direction.

The sluice tube consists of an outer casing of rolled sheet metal, within which, a removable inner tube 38 is positioned. The inner tube consists of a series of sections telescopically fitted together and maintained in their assembled relation by means of a series of tie rods 42. The upper extremity of the inner tube fits over a fixed inner sleeve 44 surrounding a universal joint 45 which in turn is fixed on the extremity of a universal shaft 46 driven from the eccentric shaft l6 through the medium of a drive belt It is desired to call attention to the fact that the axes of the universal joint 45 align with the axes of the hinge points 38 and 40 so that power to rotate the tube 31 will not be disturbed, regardless of the angle of the sluice tube. The sluice tube is rotatably mounted in ring bearings 41 at its upper extremity and in a bearing collar 49 adjacent its lower extremity. To reduce friction the bearing collar 43 is preferably provided with hearing balls 50. The bearing collar 59 may be supported in any desired manner. As illustrated, it is supported in an A-frame 5| upon adjustable hangers 52 so that its elevation and direction may be readily adjusted.

The inner tube 4| is provided with a series of annular riffies 43. These riffies are preferably, but not necessarily, formed by attaching a ring of soft rubber 59, such as spongerubber, to a hoop or band 60. The assembly is then forced within the inner tube so that the rubber 59 will form a tight seal with the walls thereof. This forms a readily removable construction.

The sand from the chute 56 feeds into the collar 44 and from thence into the inner tube 38. Gravity and the incline of the tube gradually work the sand on a helical path through the length of the tube, discharging it from the lower extremity thereof. The heavier particles containing the mineral and other values collect in front of the rifiles 43. At intervals they may be removed by withdrawing and disassembling the inner tube 4|.

As thus far described, the machine may be employed for dry placer Work. In some instances the addition of water is desirable in order to wash the sand during its progress through the sluice tube. This Water may be supplied in any desired manner, for instance, a pump 53 may be mounted in the frame l0 and driven by means of a suitable belt 54 from the shaft of the blower 28. This pump discharges through a pipe 55 into the upper extremity of the sluice tube. In some instances it may be desirable to employ mercury. This mercury may be placed in front of each of the baffles 43, as shown at 56, so as to amalgamate the gold passing through the tube 31. It is preferred to form the inner tube 4| of copper and amalgamate, the entire interior thereof so as to catch all fine or flour gold.

It is desired to call attention to the fact that each size or mesh of sand is violently agitated on its own screen independently of the other sizes. This prevents the fine sand from packing between the larger particles and obstructing the air flow. It keeps all of the sand beds open so movable inner tube positioned within said first tube; removable annular rifiles in said inner tube; means for supplying sand to said inner tube; an internal collar fixed in one extremity of said first tube for receiving the extremity of said inner tube, said inner tube being formed of telescopically united sections; and means for clamping said sections together to form a complete tube.

2. In a gold saving machine: an inclined tube; means for rotating said tube; circular hoops; an annular resilient covering about said hoops, said hoops being forced into said tube with said covering in contact with the inner wall thereof to form annular rif tles.

JOHN F. POORE. 

